EVOC EC4-1812CLDNA, Manual, Page: 28 / 68

Appendix
­ 24 ­ EC4­1812CLDNA
Appendix
Watchdog Programming Guide
EC4­1812CLDNA provides a programmable watchdog timer (WDT) up to 255 levels
and time by minute or second. Watchdog timer overtime event can be programmed to
reset system or generate maskeble interrupts.
The interrupt numbers used by the motherboard are 3, 4, 5, 7, 9, 10, 11. Please change
the value of the corresponding IRQ number in PCIPnP of BIOS Setup interface into
Reserved before using.
The following describes WDT program in C language. The steps to program WDT are
as follows:
Ø
Enter WDT programming mode
Ø
Setup WDT operating mode/enable WDT/disable WDT
(1)
Enter WDT Programming Mode
#define INDEX_PORT 0x4E
#define DATA_PORT 0x4F
unsigned int tmp_reg;
unsigned int pm_base;
outportb(INDEX_PORT, 0x55);
outportb(INDEX_PORT, 0x07);
outportb(DATA_PORT, 0x0A);
outportb(INDEX_PORT, 0x30);
outportb(DATA_PORT, 0x01);
outportb(INDEX_PORT, 0x60);